Polyester which exhibits melt anisotropy is easy to shape despite its high heat resistance, and therefore has found widespread use since its invention by Mr. J. Economy and his coworkers. More recently, the polymer skeleton has been tailored to suit varied applications, resulting in diversification of polymers in their use. Difficulties are involved, however, in designing those polymers, especially with a good balance between thermal stability and processability. Approaches to the problem have been made through various combinations of mesogens and soft spacers, but none have proven to be completely satisfactory to date.